Back to EveryPatent.com
| United States Patent |
5,260,183
|
|
Ishiguro
, et al.
|
November 9, 1993
|
Silver halide photographic material
Abstract
A novel silver halide photographic material comprising at least one silver
halide emulsion layer on a support is provided, characterized in that said
emulsion layer comprises (i) silver halide grains which are at least 80
mol % silver chloride, (ii) at least one thiocyanate, (iii) at least one
cyanine dye represented by general formula (I) and (iv) at least one
compound represented by general formula (II), (III) or (IV):
##STR1##
| Inventors:
|
Ishiguro; Shoji (Kanagawa, JP);
Ikeda; Tadashi (Kanagawa, JP)
|
| Assignee:
|
Fuji Photo Film Co., Ltd. (Kanagawa, JP)
|
| Appl. No.:
|
827062 |
| Filed:
|
January 28, 1992 |
Foreign Application Priority Data
| Current U.S. Class: |
430/567; 430/572; 430/573; 430/575; 430/583; 430/587; 430/609; 430/615 |
| Intern'l Class: |
G03C 001/005; G03C 001/494 |
| Field of Search: |
430/573,587,583,609,615,567,572,575
|
References Cited
U.S. Patent Documents
| 3695888 | Oct., 1972 | Hiller | 430/573.
|
| 3809561 | May., 1974 | Ulbing | 430/573.
|
| 4026707 | May., 1977 | Obikawa | 430/615.
|
| 4400463 | Aug., 1983 | Maskasky | 430/567.
|
| 4414306 | Nov., 1983 | Wey et al. | 430/567.
|
| 4536473 | Aug., 1985 | Mihara | 430/573.
|
| 4582786 | Apr., 1986 | Ikeda | 430/615.
|
| 4837140 | Jun., 1989 | Ikeda | 430/583.
|
| 4839270 | Jun., 1989 | Kojima | 430/583.
|
| 4935337 | Jun., 1990 | Kuwashima | 430/587.
|
| 4965182 | Oct., 1990 | Mihara | 430/615.
|
| 4983508 | Jan., 1991 | Ishiguro et al. | 430/567.
|
| Foreign Patent Documents |
| 3340571 | May., 1984 | DE | 430/609.
|
| 0141027 | Dec., 1978 | JP | 430/615.
|
| 0054936 | Apr., 1982 | JP | 430/587.
|
Primary Examiner: Bowers, Jr.; Charles L.
Assistant Examiner: Letscher; Geraldine
Attorney, Agent or Firm: Sughrue, Mion, Zinn, Macpeak & Seas
Claims
What is claimed is:
1. A silver halide photographic material comprising at least one silver
halide emulsion layer on a support, wherein said emulsion layer comprising
(i) silver halide grains which are at least 80 mol % silver chloride and
for which 50% or more of the surface is 111 plane, (ii) at least one
thiocyanate, (iii) at least one cyanine dye represented by general formula
(I) and (iv) at least one compound represented by general formula (II) or
(III):
##STR12##
wherein Z.sub.11 and Z.sub.12 may be the same or different and each
represents an atomic group for forming a naphthaothiazole nucleus, a
naphthoselenazole nucleus, a quinoline nucleus, a benzothiazole nucleus, a
benzoselenazole nucleus, a benzoxazole nucleus, a naphthoxazole nucleus or
a benzimidazole nucleus, with the provisos that when Z.sub.11 and Z.sub.12
represent an atomic group for forming a heterocyclic nucleus other than
said benzimidazole nucleus that the heterocyclic nucleus may be
substituted with a lower alkyl group, a lower alkoxy group, a hydroxyl
group, a halogen atom, an aryl group, an acylamino group, a carboxy group
or a lower alkoxy carbonyl group, and that when Z.sub.11 and Z.sub.12
represent an atomic group for forming said benzimidazole nucleus that the
heterocyclic nucleus may be substituted with a halogen atom, a cyano
group, a carboxy group, a lower alkoxy carbonyl group or a perfluoroalkyl
group; R.sub.11 and R.sub.12 may be the same or different and each
represents a alkyl group which may be substituted with a sulfo group, a
carboxy group, a hydroxyl group, an aryloxy group, an acyl group, a
carbamoyl group or an acylamino group; R.sub.15 represents a hydrogen atom
or R.sub.15 may be connected to R.sub.12 to form a 5- or 6-membered ring;
R.sub.13 represents a hydrogen atom or may be connected to R.sub.11 to
form a 5- or 6-membered ring; R.sub.14 represents a hydrogen atom or a
substituted or unsubstituted lower alkyl group; X.sub.11 represents an ion
required to neutralize the electrical charge of the compound of formula
(I); l.sub.11 represents an integer 0, 1 or 2, with the proviso that when
l.sub.11 is 2, R.sub.15 on the third carbon atom of the methine chain may
represent a substituted or unsubstituted lower alkyl group or two R.sub.14
groups may be connected to each other to form a 6-membered carbon ring;
and m.sub.11 represents an integer 0 or 1, with the proviso that when the
compound of formula (I) is an intramolecular salt, m.sub.11 is 0;
##STR13##
wherein R.sub.21, R.sub.22, R.sub.23 and R.sub.24 may be the same or
different and each represents a hydrogen atom, an alkyl group which may be
substituted, an aryl group which may be substituted, an amino group which
may be substituted, a hydroxyl group, an alkoxy group, an alkylthio group,
a carbamoyl group which may be substituted, a halogen atom, a cyano group,
a carboxyl group, an alkoxycarbonyl group or a heterocyclic group; and
R.sub.21 and R.sub.22 or R.sub.22 and R.sub.23 may be connected to each
other to form a 5- or 6-membered ring, with the proviso that at least one
of R.sub.21 and R.sub.23 represents a hydroxyl group.
2. A silver halide photographic material as claimed in claim 1, wherein
said silver halide grains are formed in the presence of a silver halide
growth modifier comprising a bispyridinium salt compound.
3. A silver halide photographic material as claimed in claim 1, wherein
said emulsion contains a compound represented by general formula (II).
4. A silver halide photographic material as claimed in claim 1, wherein
said emulsion contains a compound represented by general formula (III).
Description
FIELD OF THE INVENTION
The present invention relates to a spectrally sensitized photographic
silver halide emulsion. More particularly, the present invention relates
to a spectrally sensitized high silver chloride content silver halide
photographic material which is sensitive particularly to visible light and
infrared radiation.
BACKGROUND OF THE INVENTION
In recent times, it has been eagerly desired in the photographic industry
to shorten access time. Thus, there has been a keen desire to develop a
silver halide photographic material suitable for ultrarapid processing,
particularly a silver halide emulsion for use in the preparation thereof.
Silver halides comprising silver bromide as the main component which have
heretofore been mainly used are fundamentally unfavorable for rapid
processing because the bromine ions released during development are
development inhibiting. For ultrarapid processing, silver halides
comprising silver chloride as the main component may be preferably used.
When the silver chloride content of the silver halide grains is increased,
the water solubility of the grains is also increased, making it possible
to develop and fix the light-sensitive material in a shorter period of
time. Thus, a silver halide emulsion suitable for ultrarapid processing
can be obtained.
However, silver halide grains having a high silver chloride content
(hereinafter referred to as "high silver chloride content grains") are
disadvantageous in that they normally can easily become 100 plane cubic
grains which can be fast developed but can easily be fogged and exhibit a
low sensitivity.
Further, the inherent absorption range of high silver chloride content
grains is in a short wavelength range. In order to make the high silver
chloride content grains absorb visible light and/or infrared radiation in
a longer wavelength range and render the high silver chloride content
grains sensitive also to the wavelength range, it is necessary to subject
the high silver chloride content grains to spectral sensitization.
However, even if spectrally sensitized with a compound commonly applied to
emulsions comprising silver bromide as a main component, a silver chloride
emulsion having a silver chloride content of 80 mol % or more normally
exhibits poor absorption and remarkably poor spectral sensitizability.
This is even more true when the silver chloride content is 95 mol % or
more. Such compounds for spectral sensitization are normally methine dyes.
In particular, cyanine dyes which provide emulsions having silver bromide
as a main component with an extremely good spectral sensitizability have
such a tendency. Among cyanine dyes, many compounds which form
J-aggregates and provide so-called J-band sensitization in an emulsion
comprising silver bromide as a main component to give a high spectral
sensitivity have been recognized. This J-band sensitization is an
essential technique for giving a high trapping of light of a specific
wavelength (such as laser light) or for providing a light-sensitive
material or color light-sensitive material sensitized to light of a
specific wavelength range. However, compared to grains comprising silver
bromide as a main component, high silver chloride content grains ca barely
form such J aggregates and thus cannot benefit from J-band sensitization.
Moreover, high silver chloride content grains can easily become cubic
grains, and an elaborate technique is needed to obtain grains other than
cubic grains such as regular grain, e.g., octahedron having 111 plane and
tetrdecahedron and tabular grains from high silver chloride content
grains. In order to obtain such grains, modifiers for the growth of high
silver chloride content grains are often used. For example, F. H. Claes et
al teach in "Crystal Habit Modification of AgCl by Impurities Determining
the Solvation", The Journal of Photographic Science, Vol. 21, pp. 39-50,
1973, and "Influence of the Habit of Silver Halide Crystals on the
Absorption Spectra of Adsorbed Sensitizing", The Journal of Photographic
Science, Vol. 21, pp. 85-92, 1973, the formation of silver chloride
crystals having 110 plane and 111 plane with various grain growth
modifiers such as purine derivatives and thiourea derivatives. F. H. Claes
et al reported that J-band can be easily developed on a 100 plane and M-
and D-band can be easily developed on 110 and 111 planes. JP-B-55-42737
(the term "JP-B" as used herein means an "examined Japanese patent
publication") discloses the formation of dodecahedral silver chloride
grains having a 110 plane with imidazole derivatives. U.S. Pat. No.
4,400,463 discloses the formation of tabular silver chloride grains having
111 plane as a main plane with adenine and
poly(3-thiapentylmethacrylate)-co-acrylate-co-sodium
2-methacryloyloxyethyl-1-sulfonate. U.S. Pat. No. 4,801,523 discloses the
formation of octahedral and tabular silver chloride grains having 111
plane with adenine derivatives. JP-A-62-218959, JP-A-63-213836, and
JP-A-63-218938 (the term "JP-A" as used herein means an "unexamined
published Japanese patent application") disclose the formation of tabular
silver chloride grains with thiourea derivatives. U.S. Pat. No. 4,225,666
discloses the formation of octahedral silver chloride grains having a 111
plane with merocyanine dyes. However, the silver chloride grains formed
with such grain growth modifiers have a small amount of modifiers left on
the surface thereof, and these modifiers strongly inhibit the adsorption
of the spectral sensitizer which must be used to provide spectral
sensitization, providing only a low spectral sensitivity or making the
grains extremely foggable. Further, if a specific merocyanine dye is used
as modifier, it causes spectral sensitization, providing sensitization in
an unnecessary wavelength range and inhibiting sensitization in the
desired wavelength range with a spectral sensitizing dye. The various
disadvantages disable the silver halide grains used for silver halide
light-sensitive materials.
One of the inventors discloses in JP-A-2-000032 that octahedral and tabular
silver chloride grains having a 111 plane free from these disadvantages
can be formed with bispyridinium salt derivatives as silver chloride grain
growth modifiers. These modifiers can be easily removed after the
formation of the grains. Therefore, the above cited invention is an
excellent approach by which octahedral and tabular silver chloride grains
having a 111 plane and having no modifiers left thereon can be obtained.
Unlike cubic grains having a 100 plane, these grains can be easily
subjected to chemical sensitization such as gold and sulfur sensitization
without being fogged to provide a high sensitivity silver chloride
emulsion. However, as taught by F. H. Claes in the above cited references,
even if no silver chloride grain growth modifiers remain, high silver
chloride content grains having a 111 plane barely form J-aggregates and
exhibit a remarkably poor adsorption of cyanine dyes which are extremely
important for the production of silver halide light-sensitive materials as
compared to silver halide grains comprising silver bromide as a main
component and cubic silver chloride grains having a 100 plane, imposing
great restrtictions on spectral sensitization. Therefore, if an approach
can be found which enables sufficient J-band spectral sensitization in a
high silver chloride content emulsion having a 111 plane, a silver halide
photographic emulsion and a silver halide light-sensitive material are
obtained which exhibit a higher spectral sensitivity in a desired
wavelength range and which can be subjected to ultrarapid processing.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a high silver
chloride content emulsion having a high spectral sensitivity, particularly
a high silver chloride emulsion having a high spectral sensitivity
attained by J-band sensitization.
It is another object of the present invention to provide a high sensitivity
high silver chloride content emulsion having a high 111 plane proportion
which has been subjected to J-band spectral sensitization.
It is a further object of the present invention to provide a high
sensitivity high silver chloride content emulsion which can be subjected
to ultrarapid processing and has been subjected to J-band spectral
sensitization and a silver halide light-sensitive material prepared
therefrom.
These and other objects of the present invention will become more apparent
from the following detailed description and examples.
These objects of the present invention are accomplished with a silver
halide photographic material comprising at least one silver halide
emulsion layer on a support, characterized in that the emulsion layer
comprises (i) silver halide grains which are at least 80 mol % silver
chloride, (ii) at least one thiocyanate, (iii) at least one cyanine dye
represented by general formula (I) and (iv) at least one compound
represented by general formula (II), (III) or (IV):
##STR2##
wherein Z.sub.11 and Z.sub.12 may be the same or different and each
represents a 5- or 6-membered nitrogen-containing heterocyclic
nucleus-forming atom group ; l.sub.11 represents an integer 0, 1 or 2;
R.sub.11 and R.sub.12 may be the same or different and each represents an
alkyl or alkenyl group which may be substituted; R.sub.13 and R.sub.15
each represents a hydrogen atom; R.sub.13 may be connected to R.sub.11 to
form a 5- or 6-membered ring; R.sub.15 may be connected to R.sub.12 to
form a 5- or 6-membered ring; R.sub.14 represents a hydrogen atom or a
lower alkyl group which may be substituted; X.sub.11 represents an ion
required to neutralize the electrical charge of the dye; and m.sub.11
represents an integer 0 or 1, with the provisos that when l.sub.11 is 2,
R.sub.15 on the third carbon atom of the methine chain may represent a
lower alkyl group which may be substituted, that when 1.sub.11 is 2, the
R.sub.14 groups which are different from each other may be connected to
each other to form a 6-membered carbon ring, and that when the compound is
an intramolecular salt, m.sub.11 is 0;
##STR3##
wherein R.sub.21, R.sub.22, R.sub.23 and R.sub.24 may be the same or
different and each represents a hydrogen atom, an alkyl group which may be
substituted, an aryl group which may be substituted, an amino group which
may be substituted, a hydroxyl group, an alkoxy group, an alkylthio group,
a carbamoyl group which may be substituted, a halogen atom, a cyano group,
a carboxyl group, a alkoxycarbonyl group or a heterocyclic group; and
R.sub.21 and R.sub.22 or R.sub.22 and R.sub.23 may be connected to each
other to form a 5- or 6-membered ring, with the proviso that at least one
of R.sub.21 and R.sub.23 represents a hydroxyl group;
##STR4##
wherein R.sub.51 represents a hydrogen atom or an alkyl group; X
represents a monovalent group obtained by removing a hydrogen atom from a
compound represented by general formula (II) or (III); and J represents a
divalent linking group.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages and further description will now be
discussed in connection with the drawings in which:
FIG. 1 is a graph illustrating the transmission absorption spectrum of
Specimens 1-13 (broken line), 1-14 (dotted line) and 1-16 (chain line) of
Example 1;
FIG. 2 is a graph illustrating the spectral sensitivity distribution
spectrum of Specimens 2-1 (solid line), 2-2 (dotted line) and 2-3 (chain
line) of Example 2 which give a density of 0.3;
FIG. 3 is a graph illustrating the spectral sensitivity distribution
spectrum of Specimens 2-7 (solid line), 2-8 (dotted line) and 2-9 (chain
line) of Example 2 which give a density of 0.3;
FIG. 4 is a graph illustrating the transmission absoption spectrum of
Specimens 2-1 (solid line), 2-2 (dotted line) and 2-3 (chain line) of
Example 2;
FIG. 5 is a graph illustrating the transmission absoption spectrum of
Specimens 2-7 (solid line), 2-8 (dotted line) and 2-9 (chain line) of
Example 2;
FIG. 6 is a graph illustrating the transmission absoption spectrum of
Specimens 3-5 (broken line), 3-6 (dotted line) and 3-8 (chain line) of
Example 3;
FIG. 7 is a graph illustrating the spectral sensitivity distribution
spectrum of Specimens 4-1 (solid line), 4-2 (dotted line) and 4-4 (chain
line) of Example 4 which gives a density of 0.3;
FIG. 8 is a graph illustrating the transmission absoption spectrum of
Specimens 4-1 (broken line), 4-2 (solid line), 4-3 (dotted line) and 4-4
(chain line) of Example 4;
FIG. 9 is a graph illustrating the transmission absoption spectrum of
Specimens 5-1 (broken line), 5-2 (solid line), 5-3 (dotted line), and 5-4
(chain line) of Example 5.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be further described hereinafter.
In the general formula (I), Z.sub.11 and Z.sub.12 may be the same or
different and each represents a 5- or 6-membered nitrogen-containing
heterocyclic nucleus-forming atom group, and l.sub.11 represents an
integer 0, 1 or 2. Preferred examples of the heterocyclic nucleus
represented by Z.sub.11 and Z.sub.12 which may be the same or different,
if l.sub.11 is 0 or 1, include thiazole, benzothiazole, naphthothiazole,
dihydronaphthothiazole, selenazole, benzoselenazole, naphthoselenazole,
dihydronaphthoselenazole, oxazole, benzoxazole, naphthoxazole,
benzimidazole, naphthoimidazole, pyridine, quinoline,
imidazo[4,5-b]quinoxaline, and 3,3-dialkylindolenine. If l.sub.11 is 2,
preferred examples of Z.sub.11 and Z.sub.12 which may be the same or
different include benzothiazole, benzoselenazole, benzoxazole,
naphthoxazole, benzimidazole, and naphthoimidazole.
The nitrogen-containing heterocyclic nucleus represented by Z.sub.11 or
Z.sub.12 may contain one or more substituents. Preferred examples of
substituents for the nitrogen-containing heterocyclic nucleus of Z.sub.11
or Z.sub.12 which represents nucleus other than benzimidazole and
naphthoimidazole include a lower alkyl group (e.g., a lower alkyl group
which may be branched or further contain substituents such as a hydroxyl
group, a halogen atom, an aryl group, an aryloxy group, an arylthio group,
a carboxyl group, an alkoxy group, an alkylthio group and an
alkoxycarbonyl group, more preferably an alkyl group containing 8 or less
carbon atoms, such as methyl, ethyl, butyl, chloroethyl,
2,2,3,3-tetrafluoropropyl, hydroxyl, benzyl, carboxypropyl, methoxyethyl,
ethylthioethyl and ethoxycarbonylethyl), a lower alkoxy group (e.g., a
lower alkoxy group which may contain substituents such as those described
with reference to the above mentioned lower alkyl group, more preferably
an alkoxy group containing 8 or less carbon atoms, such as methoxy,
ethoxy, pentyloxy, ethoxymethoxy, methylthioethoxy, phenoxyethoxy,
hydroxyethoxy and chloropropoxy), a hydroxyl group, a halogen atom, an
aryl group (e.g., phenyl, tolyl, anisyl, chlorophenyl, carboxyphenyl), an
aryloxy group (e.g., tolyloxy, anisyloxy, phenoxy, chlorophenoxy), an
arylthio group (e.g., tolylthio, chlorophenylthio, phenylthio), a lower
alkylthio group (e.g., lower alkylthio group which may be further
substituted by substituents such as those described with reference to the
above mentioned lower alkyl group, more preferably an alkylthio group
containing 8 or less carbon atoms, such as methylthio, ethylthio,
hydroxyethylthio, carboxyethylthio, chloroethylthio, benzylthio), an
acylamino group (more preferably an acylamino group containing 8 or less
carbon atoms, such as acetylamino, benzoylamino, methanesulfonylamino,
benzenesulfonylamino), a carboxyl group, a lower alkoxycarbonyl group
(more preferably an alkoxycarbonyl group containing 6 or less carbon
atoms, such as ethoxycarbonyl and butoxycarbonyl), a perfluoroalkyl group
(more preferably a perfluoroalkyl group containing 5 or less carbon atoms,
such as trifluoromethyl and difluoromethyl), and an acyl group (more
preferably an acyl group containing 8 or less carbon atoms, such as
acetyl, propionyl, benzoyl and benzenesulfonyl). Preferred examples of
substituents for the nitrogen-containing heterocyclic nucleus of Z.sub.11
or Z.sub.12 which represents benzimidazole or naphthoimidazole if l.sub.11
is 0 or 1, include a halogen atom, a cyano group, a carboxyl group, a
lower alkoxycarbonyl group (more preferably an alkoxycarbonyl group
containing 6 or less carbon atoms, such as ethoxycarbonyl and
butoxycarbonyl), a perfluoroalkyl group (more preferably a perfluoroalkyl
group containing 5 or less carbon atoms, such as trifluoromethyl and
difluoromethyl), and an acyl group (more preferably an acyl group
containing 8 or less carbon atoms, such as acetyl, propionyl, benzoyl, and
benzenesulfonyl). Preferred examples of substituents for the
nitrogen-containing heterocyclic nucleus of Z.sub.11 or Z.sub.12 which
represents benzimidazole or naphthoimidazole if l.sub.11 is 2 include a
halogen atom, a cyano group, a carboxyl group, and a lower alkoxycarbonyl
group containing 5 or less carbon atoms.
Specific examples of the nitrogen-containing heterocyclic nucleus
represented by Z.sub.11 or Z.sub.12 include benzothiazole,
5-methylbenzothiazole, 6-methylbenzothiazole, 5-ethylbenzothiazole,
5,6-dimethylbenzothiazole, 5-methoxybenzothiazole, 6-methoxybenzothiazole,
5-butoxybenzothiazole, 5,6-dimethoxybenzothiazole,
5-methoxy-6-methylbenzothiazole, 5 chlorobenzothiazole,
5-chloro-6-methylbenzothiazole, 5-phenylbenzothiazole,
5-acetylaminobenzothiazole, 6-propionylaminobenzothiazole,
5-hydroxybenzothiazole, 5-hydroxy-6-methylbenzothiazole,
5-ethoxycarbonylbenzothiazole, 5-carboxybenzothiazole,
naphtho[1,2-d]thiazole, naphtho[2,1-d]thiazole,
5-methylnaphtho[1,2-d]thiazole, 8-methoxynaphtho[1,2-d]thiazole,
8,9-dihydronaphthothiazole, 3,3-diethylindolenine, 3,3-dipropylindolenine,
3,3-dimethylindolenine, 3,3,5-trimethylindolenine, benzoselenazole,
5-methylbenzoselenazole, 6-methylbenzoselenazole,
5-methoxybenzoselenazole, 6-methoxybenzoselenazole,
5-chlorobenzoselenazole, 5,6-dimethylbenzoselenazole,
5-hydroxybenzoselenazole, 5-hydroxy-6-methylbenzoselenazole,
5,6-dimethoxybenzoselenazole, 5-ethoxycarbonylbenzoselenazole,
naphtho[1,2-d]selenazole, naphtho[2,1-d]selenazole, benzoxazole,
5-hydroxybenzoxazole, 5-methoxybenzoxazole, 5-phenylbenzoxazole,
5-phenethylbenzoxazole, 5-phenoxybenzoxazole, 5-chlorobenzoxazole,
5-chloro-6-methylbenzoxazole, 5-phenylthiobenzoxazole,
6-ethoxy-5-hydroxybenzoxazole, 6-methoxybenzoxazole,
naphtho[1,2-d]oxazole, naphtho[2,1-d]oxazole, naphtho[2,3-d]oxazole,
1-ethyl-5-cyanobenzimidazole, 1-ethyl-5-chlorobenzimidazole,
1-ethyl-5,6-dichlorobenzimidazole, 1-ethyl-6-chloro-5-cyanobenzimidazole,
1-ethyl-6-chloro-5-trifluoromethylbenzimidazole,
1-ethyl-5,6-dichlorobenzimidazole, 1-ethyl-6-fluoro-5-cyanobenzimidazole,
1-propyl-5-butoxycarbonylbenzimidazole,
1-benzyl-5-methylsulfonylbenzimidazole,
1-allyl-5-chloro-6-acetylbenzimidazole, 1-ethylnaphtho-[1,2-d]imidazole,
1-ethylnaphtho[2,3-d]imidazole, 1-ethyl-6-chloronaphtho[2,3-d]imidazole,
2-quinoline, 4-quinoline, 8-fluoro-4-quinoline, 6-methyl-2-quinoline,
6-hydroxy-2-quinoline, and 6-methoxy-2-quinoline.
R.sub.11 and R.sub.12 may be the same or different and each represents an
alkyl or alkenyl group containing 10 or less carbon atoms which may be
substituted. Preferred examples of the substituents for the alkyl group
and alkenyl group include a sulfo group, a carboxyl group, a halogen atom,
a hydroxyl group, an alkoxy group containing 6 or less carbon atoms, an
aryl group containing 8 or less carbon atoms (e.g., phenyl, tolyl,
sulfophenyl, carboxyphenyl), a heterocyclic group (e.g., furyl, chenyl),
an aryloxy group containing 8 or less carbon atoms which may be
substituted (e.g., chlorophenoxy, phenoxy, sulfophenoxy, hydroxyphenoxy),
an acyl group containing 8 or less carbon atoms (e.g., benzenesulfonyl,
methanesulfonyl, acetyl, propionyl), an alkoxycarbonyl group containing 6
or less carbon atoms (e.g., ethoxycarbonyl, butoxycarbonyl), a cyano
group, an alkylthio group containing 6 or less carbon atoms (e.g.,
methylthio, ethylthio), an arylthio group containing 8 or less carbon
atoms which may be substituted (e.g., phenylthio, tolylthio), a carbamoyl
group containing 8 or less carbon atoms which may be substituted (e.g.,
carbamoyl, N-ethylcarbamoyl), and an acylamino group containing 8 or less
carbon atoms (e.g., acetylamino, methanesulfonylamino). There may be one
or more such substituents to R.sub.11 and R.sub.12.
Specific examples of the group represented by R.sub.11 or R.sub.12 include
a methyl group, an ethyl group, a propyl group, an allyl group, a pentyl
group, a hexyl group, a methoxyethyl group, an ethoxyethyl group, a
phenethyl group, a tolylethyl group, a sulfophenethyl group, a
2,2,2-trifluoroethyl group, a 2,2,3,3-tetrafluoropropyl group, a
carbamoylethyl group, a hydroxyethyl group, a 2-(2-hydroxyethoxy)ethyl
group, a carboxymethyl group, a carboxyethyl group, an
ethoxycarbonylmethyl group, a sulfoethyl group, a 2-chloro-3-sulfopropyl
group, a 3-sulfopropyl group, a 2-hydroxy-3-sulfopropyl group, a
3-sulfobutyl group, a 4-sulfobutyl group, a
2-(2,3-dihydroxypropyloxy)ethyl group, and a
2-[2-(3-sulfopropyloxy)ethoxy]ethyl group.
R.sub.13 and R.sub.15 each represents a hydrogen atom. R.sub.13 and
R.sub.11, and R.sub.15 and R.sub.12 may be connected to each other to form
a 5- or 6-membered ring. Further, if l.sub.11 is 2, R.sub.15 on the third
carbon atom of the methine chain may also represent a lower alkyl group
(lower alkyl group which may be substituted, e.g., methyl, ethyl, propyl,
methoxyethyl, benzyl, phenethyl).
R.sub.14 represents a hydrogen atom or a lower alkyl group (a lower alkyl
group which may be substituted, e.g., methyl, ethyl, propyl, methoxyethyl,
phenethyl, preferably an alkyl group containing 5 or less carbon atoms).
Moreover, if l.sub.11 is 2, the two R.sub.14 groups may be connected to
each other to form a 6-membered carbon ring.
X.sub.11 represents an ion required to neutralize the electrical charge of
the dye.
The suffix m.sub.11 represents an integer 0 or 1. If the compound
represented by general formula (I) is an intramolecular salt, m.sub.11 is
0.
In general formulae (II) and (III), R.sub.21 and R.sub.22 may be the same
or different, and R.sub.23 and R.sub.24 may be the same or different.
R.sub.21, R.sub.22, R.sub.23, and R.sub.24 each represents a hydrogen
atom, a C.sub.1-20 straight-chain, cyclic or branched substituted or
unsubstituted alkyl group, a monocyclic or bicyclic substituted or
unsubstituted aryl group, a substituted or unsubstituted amino group, a
hydroxyl group, a C.sub.1-20 alkoxy group, a C.sub.1-6 alkylthio group, a
carbamoyl group which may be substituted by an aliphatic or aromatic
group, a halogen atom, a cyano group, a carboxyl group, a C.sub.2-20
alkoxycarbonyl group, or a heterocyclic group containing a 5- or
6-membered ring which contains hetero atoms such as nitrogen, oxygen or
sulfur. R.sub.21 and R.sub.22 or R.sub.22 and R.sub.23 may be connected to
each other to form a 5- or 6-membered ring, with the proviso that at least
one of R.sub.21 and R.sub.23 is a hydroxyl group.
R.sub.51 represents a hydrogen atom or alkyl group. X represents a
monovalent group obtained by removing one hydrogen atom from the compound
represented by general formula (II) or (III) (e.g., compound obtained by
removing one hydrogen atom from the portion of R.sub.21, R.sub.22,
R.sub.23 or R.sub.24 in general formula (II) or (III)). J represents a
divalent linking group.
Examples of the above mentioned unsubstituted alkyl groups include a methyl
group, an ethyl group, an n-propyl group, an i-propyl group, a t-propyl
group, an n-butyl group, a t-butyl group, a hexyl group, a cyclohexyl
group, a cylopentylmethyl group, an octyl group, a dodecyl group, a
tridecyl group, and a heptadecyl group. Examples of the substituents
contained in the above mentioned substituted alkyl group include a
monocyclic or bicyclic aryl group, a heterocyclic group, a halogen atom, a
carboxyl group, a C.sub.2-6 alkoxycarbonyl group, an alkoxy group
containing 19 or less carbon atoms, and a hydroxyl group. Specific
examples of the substituted alkyl group include a benzyl group, a
phenethyl group, a chloromethyl group, a 2-chloroethyl group, a
trifluoromethyl group, a carboxymethyl group, a 2-carboxyethyl group, a
2-(methoxycarbonyl)ethyl group, an ethoxycarbonylmethyl group, a
2-methoxyethyl group, a hydroxymethyl group, and a 2-hydroxyethyl group.
Examples of the above mentioned unsubstituted aryl group include a phenyl
group and a naphthyl group. Examples of the substituents contained in the
above mentioned substituted aryl group include an alkyl group containing 4
or less carbon atoms, a halogen atom, a carboxyl group, a cyano group, an
alkoxycarbonyl group containing 6 or less carbon atoms, a hydroxyl group,
and an alkoxy group containing 6 or less carbon atoms. Specific examples
of the substituted aryl group include a p-tolyl group, an m-tolyl group, a
p-chlorophenyl group, a p-bromophenyl group, an o-chlorophenyl group, an
m-cyanophenyl group, a p-carboxyphenyl group, an o-carboxyphenyl group, an
o-(methoxycarbonyl)phenyl group, a p-hydroxyphenyl group, a
p-methoxyphenyl group, and an m-ethoxyphenyl group.
Examples of the substituents contained in the above mentioned substituted
amino group include an alkyl group (e.g., methyl, ethyl, butyl), and an
acyl group (e.g., acetyl, propionyl, benzoyl, methylsulfonyl). Specific
examples of such a substituted amino group include a dimethylamino group,
a diethylamino group, a butylamino group, and an acetylamino group.
Specific examples of the above mentioned alkoxy group include a methoxy
group, an ethoxy group, a butoxy group, and a heptadecyloxy group.
Specific examples of the above mentioned alkylthio group include a
methylthio group, an ethylthio group, and a hexylthio group.
The above mentioned carbamoyl group may contain one or two of alkyl groups
containing 20 or less carbon atoms and bicyclic or monocyclic aryl groups
as substituents. Specific examples of such a substituted carbamoyl group
include a methylcarbamoyl group, a dimethylcarbamoyl group, an
ethylcarbamoyl group, and a phenylcarbamoyl group.
Specific examples of the above mentioned alkoxycarbonyl group include a
methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl
group.
Specific examples of the above mentioned halogen atom include a fluorine
atom, a chlorine atom, and a bromine atom.
The above mentioned heterocyclic group may be monocyclic or may contain a
bicyclic or tricyclic condensed ring. Specific examples of such a
heterocyclic group include a furyl group, a pyridyl group, a
2-(3-methyl)benzothiazolyl group, and a 1-benzotriazolyl group.
In the above mentioned substituted alkyl group, if the substituent
contained in the substituted alkyl group represented by R.sub.24 is a
heterocyclic group, it is preferably a substituent represented by general
formula (V):
##STR5##
wherein R.sub.21, R.sub.22 and R.sub.23 are as defined above; and n
represents an integer 2, 3 or 4.
Preferred among the sensitizing dyes represented by general formula (I) are
those wherein Z.sub.11 and Z.sub.12 both represent a heterocyclic
nucleus-forming atom group such as benzothiazole, naphthothiazole,
dihydronaphthothiazole, benzoselenazole, naphthoselenazole,
dihydronaphtho-selenazole, benzoxazole, naphthoxazole, benzimidazole and
naphthoimidazole [the heterocyclic nucleus represented by Z.sub.11 or
Z.sub.12 may contain one or more substituents as mentioned above;
particularly preferred examples of the substituents for the heterocyclic
group wherein Z.sub.11 and Z.sub.12 each represents nucleus other than a
benzimidazole nucleus or naphthoimidazole nucleus include a methyl group,
an ethyl group, a propyl group, a methoxy group, an ethoxy group, an
acetylamino group, a phenyl group, a tolyl group, and a chlorine atom;
particularly preferred examples of the substituents for the heterocyclic
group wherein Z.sub.11 and Z.sub.12 each represents benzimidazole nucleus
or naphthoimidazole nucleus include a chlorine atom, a fluorine atom, a
cyano group, a carboxyl group, and a lower alkoxycarbonyl group containing
5 or less carbon atoms], and R.sub.13 and R.sub.15 connected to a methine
group adjacent to the heterocyclic nuclei each represents a hydrogen atom.
Other preferred examples of the sensitizing dyes include those represented
by the general formula (I) wherein l.sub.11 represents 1, and at least one
of the heterocyclic groups represented by Z.sub.11 and Z.sub.12 represents
a benzimidazole or naphthoimidazole nucleus-forming atom group, wherein
R.sub.14 represents a hydrogen atom, and the heterocyclic nuclei
represented by Z.sub.11 and Z.sub.12 each represents a nucleus-forming
atom group other than benzimidazole nucleus or naphthoimidazole nucleus,
and wherein R.sub.14 is an ethyl group, a propyl group, or a phenethyl
group.
A technique for distributing silver thiocyanate on cubic silver chloride
grains and tabular silver chloride grains having opposing parallel 111
main crystal planes is disclosed in JP-B-2-21572, and JP-A-59-162540. In
that reference, an aqueous solution of silver nitrate and an aqueous
solution of sodium thiocyanate are simultaneously added to host silver
halide grains having a face-centered cubic rock salt structure in a double
jet process so that silver thiocyanate is epitaxially precipitated on the
edge or corner of the host grains to obtain a high inherent sensitivity.
It is true that the precipitation of silver thiocyanate on high silver
chloride content host grains can provide a higher sensitivity than the
original host grains as taught by the above cited patents. However, this
approach remarkably inhibits chemical sensitization, and the sensitivity
obtained after chemical sensitization is not necessarily higher than that
of the host grains. In particular, as demonstrated by the examples in the
above cited patents, if a large amount of silver thiocyanate is used based
on the host grains, the sensitivity obtained after chemical sensitization
is lower than that of the host grains. Further, the above cited
JP-A-59-162540 teaches in Example 6 an approach which comprises
epitaxially precipitating silver thiocyanate on host cubic silver chloride
grains, and then covering the core again by silver chloride as a shell.
This teaching does not suggest that the precipitation of silver
thiocyanate on silver chloride provides improvements in the adsorption of
cyanine dye, particularly difficult J-band spectral sensitization.
Moreover, in the above cited patent, the results of spectral sensitization
are not for silver chloride grains but for host grains comprising silver
bromide as a main component.
The inventors found that the combined use of a cyanine dye represented by
general formula (I) and a thiocyanate on high silver content grains
provides easy improvements in J-band spectral sensitization, which has
been heretofore difficult. In particular, it was found that even high
silver chloride content grains having a high 111 plane proportion, which
has herefore rarely been subjected to J-band spectral sensitization, can
be easily subjected to J-band spectral sensitization as in silver halide
grains comprising silver bromide as main component. It was further found
that the incorporation of at least one tetrazaindene compound represented
by general formula (II), (III) or (IV) in the high silver chloride content
emulsion can provide a high spectral sensitivity, and if optionally
combined with chemical sensitization, can provide a high J-band spectral
sensitization.
Specific examples of the sensitizing dye represented by general formula (I)
will be set forth below, but the present invention should not be construed
as being limited thereto:
##STR6##
The sensitizing dye of general formula (I) to be used in the present
invention is a known compound. The synthesis of the sensitizing dye of
general formula (I) can be accomplished by any suitable method as
disclosed in JP-A-52-104917, JP-B-48-25652, JP-B-57-22368, F. M. Hamer,
The Chemistry of Heterocyclic Compounds, Vol. 18, The Cyanine Dyes and
Related Compounds, A. Weissberger ed., Interscience, New York, 1964, D. M.
Sturmer, The Chemistry of Heterocyclic Compounds, Vol. 30, A. Weissberger
and E. C. Taylor ed., John Willy, New York, p. 441, and Japanese patent
application no. 2-270164.
In order to incorporate the cyanine dye of general formula (I) in the
silver halide emulsion of the present invention, one may be directly
disperse it in the emulsion or incorporate it in the emulsion in the form
of solution of water, methanol, ethanol, propanol, acetone, methyl
cellosolve, 2,2,3,3-tetrafluoropropanol, 2,2,2-trifluoroethanol,
3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol,
N,N-dimethylformamide, etc., either singly or in admixture.
Further, a method as disclosed in U.S. Pat. No. 3,469,987 may be used which
comprises dissolving a dye in an organic volatile solvent, dispersing the
solution in water or a hydrophilic colloid, and then adding the dispersion
to an emulsion. A method as disclosed in JP-B- 46-24185 may be used which
comprises directly dispersing a water-insoluble dye in a water-soluble
solvent without dissolving it, and then adding the dispersion to an
emulsion. A method as disclosed in JP-B-44-23389, JP-B-44-27555 and
JP-B-57-22091 may be used which comprises incorporating a dye in an
emulsion in the form of a solution in an acid or incorporating a dye in an
emulsion in the form of an aqueous solution obtained in the presence of
acid or base. A method as disclosed in U.S. Pat. Nos. 3,822,135 and
4,006,025 may be used which comprises incorporating a dye in an emulsion
in the form of an aqueous solution or a colloidal dispersion obtained in
the presence of a surface active agent. A method as disclosed in
JP-A-53-102733 and JP-A-58-105141 may be used which comprises directly
dispersing a dye in a hydrophilic colloid, and then incorporating the
dispersion in an emulsion. A method as disclosed in JP-A-51-74624 may be
used which comprises dissolving a dye in the presence of a compound which
causes red shift, and then incorporating the solution in an emulsion.
The dissolution of such a dye in a solvent can be promoted by ultrasonic
waves.
The time during which the sensitizing dye is incorporated in the silver
halide emulsion of the present invention may be at any step in the process
for the preparation of emulsion which has heretofore been considered
suitable. For example, as disclosed in U.S. Pat. Nos. 2,735,766,
3,628,960, 4,183,756, and 4,225,666, JP-A-58-184142 and JP-A-60-196749, it
may be during the formation of silver halide grains and/or before the
desalting of silver halide grains. As disclosed in JP-A-58-113920, it may
be shortly before or during chemical ripening, or at any time or step
before the coating of an emulsion which has been subjected to chemical
ripening. Further, as disclosed in U.S. Pat. No. 4,225,666 and
JP-A-58-7629, a sensitizing dye, either singly or in combination with one
having a different structure, may be batchwise incorporated in the system
during the formation of grains and during the chemical ripening of grains
or after the completion of the chemical ripening of grains, or before or
during the chemical ripening of grains and after the completion of the
chemical ripening of grains. Moreover, the kind of the compounds to be
batchwise added and the combination thereof may be altered.
The addition amount of the sensitizing dye of general formula (I) depends
on the shape and size of silver halide grains and is normally in the range
of 4.times.10.sup.-6 to 8.times.10.sup.-3 mol per mol of silver halide.
For example, if the size of silver halide grains is in the range of 0.2 to
1.3 .mu.m, the amount is preferably in the range of 5.times.10.sup.-5 to
2.times.10.sup.-3 mol and the range corresponding to a percentage grain
surface coverage of 20 to 100%, more preferably 30 to 90%, per mol of
silver halide.
The thiocyanate compound to be used in the present invention may be used in
the form of an inorganic or organic salt such as alkaline metal salt of
thiocyanic acid (such as potassium thiocyanate and sodium thiocyanate),
alkali earth metal salt of thiocyanic acid (such as calcium thiocyanate
and magnesium thiocyanate), silver thiocyanate, and ammonium salt of
thiocyanic acid (such as ammonium thiocyanate).
The incorporation of the thiocyanate compound may be effected before, after
or at the same time as the incorporation of the cyanine dye of general
formula (I) in the silver halide emulsion. Further, the thiocyanate
compound may be added to the system continuously or batchwise between the
time before the addition of the sensitizing dye and the time after the
completion of the sensitizing dye. Thus, the time during which the
thiocyanate compound is incorporated into the system is not specifically
limited. However, the thiocyanate compound has been recognized to reduce
the inhibition of chemical sensitization on high silver chloride content
emulsion, although the degree of the reduction of the inhibition depends
on the amount of the thiocyanate compound to be incorporated. Therefore,
in order to obtain a higher sensitivity, the thiocyanate compound is
preferably added to the system after the middle phase of the chemical
sensitization.
The amount of the thiocyanate compound to be incorporated depends on the
shape and size of the silver halide grains to which it is incorporated and
is normally in the range of 2.5.times.10.sup.-5 to 2.times.10.sup.-2 mol,
preferably 5.times.10.sup.-4 to 1.5.times.10.sup.-2 mol per mol of silver
halide. For example, if the size of the silver halide grains is in the
range of 0.2 to 1.3 .mu.m, the amount is preferably in the range of 0.1 to
5 mol, more preferably 0.25 to 2 mol, per mol of silver halide lying on
the entire surface of silver halide grains.
Specific examples of the compounds represented by general formulae (II),
(III) and (IV) are set forth below, but the present invention should not
be construed as being limited thereto:
##STR7##
The synthesis of the compound represented by general formula (II), (III) or
(IV) can be accomplished by any suitable method as disclosed in
JP-A-57-211142 and U.S. Pat. No. 4,397,943.
The compound represented by general formula (IV) has molecular weight of
5.times.10.sup.3 to 3.times.10.sup.6, preferably 10.sup.4 to 10.sup.6.
In the present invention, the compound represented by general formula (II),
(III) or (IV) may be incorporated in the system in an amount of
1.times.10.sup.-5 to 0.3 mol, particularly 3.times.10.sup.-4 to 0.1 mol,
per mol of silver halide. The optimum amount of the compound to be
incorporated is preferably selected depending on the grain size of silver
halide grains, the halogen composition of silver halide grains, the method
and degree of chemical sensitization, the relationship between the
emulsion layer of the present invention and other layers, the kind of fog
inhibitor, etc. The test method for the selection of the optimum amount of
the compound is well known and can be easily effected by those skilled in
the art.
In order to incorporate the compound represented by general formula (II),
(III) or (IV) into the high silver chloride content emulsion, the same
methods as those for incorporating the cyanine dye represented by general
formula (I) can be used. For example, the compound may be directly
dispersed in the emulsion or may be dissolved in an organic solvent
miscible with water or in water, if it is water-soluble, dispersed in a
hydrophilic colloid, and then incorporating the dispersion into the
emulsion. The aqueous solution may be advantageously alkaline to promote
dissolution.
In the present invention, if the compound represented by general formula
(II), (III) or (IV) is incorporated into the silver halide emulsion, the
incorporation of the compound may be effected at any time between the
formation of silver halide grains and the coating of silver halide
emulsion, preferably after the completion of the addition of the cyanine
dye represented by general formula (I), more preferably after the
beginning of chemical ripening, particularly between the time of the
completion of chemical ripening and the time of coating.
The high silver chloride content emulsion to be used in the present
invention consists of silver halide substantially free of silver iodide
(that is, containing silver iodide in an amount of not more than 0.02 mol
%) and containing silver chloride in an amount of 80 mol % or more. The
silver chloride content is preferably in the range of 95 mol % or more.
More preferably, the high silver chloride content emulsion is pure silver
chloride.
In the spectral sensitization of grains with a cyanine dye such as those
represented by general formula (I), a water-soluble iodide such as
potassium iodide is often used in a minute amount such as 0.5 mol % or
less per mol of silver halide to promote the adsorption to the silver
halide grains or the formation of J-aggregates, providing a higher
spectral sensitizability. However, it has been known that the iodide thus
added causes the formation of an iodide portion in the vicinity of the
surface of silver halide. In the development of silver halide photographic
materials, it has been known that iodine ions released from such a iodide
portion exhibit a stronger effect of inhibiting development than the above
mentioned bromine ions. Therefore, even if such a water-soluble iodide is
used in a minute amount such as 0.5 mol % per mol of silver halide, it
becomes a great hindrance to ultrarapid processing. Further, if the
water-soluble iodide is used in a minute amount on the high silver
chloride content emulsion, it is inherently effective only for some
cyanine dyes which exhibit a relatively strong adsorption and form
J-aggregates. Moreover, if the water-soluble iodide is used in a minute
amount, it exerts a very weak effect on the high silver chloride content
grains having a 111 plane area proportion of more than 50%, and little or
no effect on the octahedral grains and tabular grains having main parallel
surfaces formed by 111 planes. The silver iodide content of not more than
0.02 mol % in the silver halide emulsion as defined in the present
invention is the minimum allowable level for ultrarapid processing and the
upper limit of amount which does not promote the adsorption of cyanine dye
and the formation of J-aggregates in silver chloride emulsions.
It can thus be said that the effects of the present invention are attained
remarkably on high silver chloride content emulsions having a high 111
plane proportion as 50% or more which hardly cause fogging and provide a
higher sensitivity by chemical sensitization than cubic grains,
particularly high silver chloride content emulsions containing octahedral
grains or tabular grains having opposing parallel main surfaces formed by
111 planes.
The high silver content emulsion to be used in the present invention
preferably exhibits an average grain size of 0.1 to 2 .mu.m, more
preferably 0.2 to 1.3 .mu.m, as calculated in terms of the diameter of the
circle equivalent in projected area. The high silver content emulsion of
the present invention may be monodisperse or polydisperse, preferably
monodisperse. The grain size distribution, which indicates the degree of
monodispersion, is preferably 0.2 or less, more preferably 0.15 or less,
as calculated in terms of the ratio (s/d) of statistical standard
deviation (s) to average grain size (d).
The high silver chloride content emulsion to be used in the present
invention may have phases differing from the core to shell, or a
multi-phase structure having junctions, or a phase which is uniform all
over the grain, or may have a mixture thereof.
The silver halide grains to be used in the present invention may have a
regular crystal form such as a cube, an octahedron, a tetradecahedron, an
irregular crystal form or a composite thereof. Alternatively, an emulsion
wherein tabular grains having a length/thickness ratio of 5 or more,
particulaly 8 or more, account for more than 50% of all grains as
calculated in terms of the projected area, may also be preferably used.
The emulsion to be used in the present invention may have a mixture of the
various crystal forms. The various emulsions may be of the surface latent
image type wherein latent images are formed mainly on the surface of
grains or the internal latent image type wherein latent images are formed
mainly inside grains.
The preparation of the photographic emulsion which can be used in the
present invention can be accomplished by any suitable method as described
in P. Glafkides, Chemie et Physique Photographique, Paul Montel (1967), G.
F. Duffin, Photographic Emulsion Chemistry, Focal Press, 1966, V. L.
Zelikman et al., Making and Coating Photographic Emulsion, Focal Press,
1964, F. H. Claes et al., The Journal of Photographic Science, (21) pp.
39-50, 1973, F. H. Claes et al., The Journal of Photographic Science, (21)
pp. 85-92, 1973, JP-B-55-42737, U.S. Pat. Nos. 4,400,463 and 4,801,523,
JP-A-62-218959, JP-A-63-213836, and JP-A-63-218938, and Japanese patent
application no. 62-291487 (corresponding to JP-A-2-32). In some detail,
the emulsion can be prepared by any of the acid process, the neutral
process, the ammonia process, etc. The reaction between a soluble silver
salt and a soluble halogen salt can be carried out by any of a single jet
process, a double jet process, a combination thereof, and the like. A
method in which grains are formed in the presence of excess silver ions
(so-called reverse mixing method) may be used. Further, a so-called
controlled double jet process, in which a pAg value of a liquid phase in
which silver halide grains are formed is maintained constant, may also be
used. According to the controlled double jet process, a silver halide
emulsion having a regular crystal form and an almost uniform grain size
can be obtained.
Further, emulsions prepared by the so-called conversion method which
comprises converting the emulsion to the silver halide already formed by
or after the completion of the formation of silver halide grains may be
used.
If an emulsion is used wherein octahedral grains or tabular grains having
111 planes as parallel main planes, particularly tabular grains with a
length/thickness ratio of 5 or more, particularly 8 or more, on which the
effects of the present invention are more remarkably exerted, account for
50% or more of all the projected area of grains, the preparation of the
high silver chloride content grains is preferably effected with a
bispyridinium salt compound as disclosed in Japanese patent application
no. 62-291487 (corresponding to JP-A-2-32) as a grain growth modifier,
particularly a 4,4'-ethylenebispyridinium salt compound.
In the process for the preparation of the silver halide grains of the
present invention, silver halide solvents may be used. Examples of the
silver halide solvents which are often used and can be used in the present
invention include thioether compounds as disclosed in U.S. Pat. Nos.
3,271,157, 3,574,628, 3,704,130, and 4,276,347, thione compounds and
thiourea compounds as disclosed in JP-A-53-144319, JP-A-53-82408, and
JP-A-55-77737, and amine compounds as disclosed in JP-A-54-100717.
Further, ammonia can be used so long as it does not exert an adverse
effect.
In the process for the preparation of the silver halide grains of the
present invention, the rate at which the silver salt solution (e.g., an
aqueous solution of silver nitrate) and the halide solution (e.g., an
aqueous solution of sodium chloride) are added, the amounts of these
solutions and the concentration of these solutions may be preferably
raised with time. For these methods, reference can be made to British Pat.
No. 1,335,925, U.S. Pat. Nos. 3,672,900, 3,650,757, and 4,242,445, and
JP-A-55-142329, JP-A-55-158124, JP-A-55-113927, JP-A-58-113928,
JP-A-58-111934, and JP-A-58-111936.
In the process for the formation or physical ripening of silver halide
grains, cadmium salt, zinc salt, lead salt, thallium salt, rhenium salt,
ruthenium salt, iridium salt or a complex salt thereof, rhodium salt or a
complex salt thereof, or iron salt or a complex salt thereof may be
present in the system. Particularly preferred among these salts are
rhenium salt, iridium salt, rhodium salt, and iron salt.
The high silver chloride content emulsion of the present invention may be
used without being subjected to chemical sensitization but may be
optionally subjected to chemical sensitization before use.
The chemical sensitization can be accomplished by a so-called gold
sensitization method with gold compounds (as disclosed in U.S. Pat. Nos.
2,448,060, 3,320,069), a sensitization method with metals such as iridium,
platinum, rhodium and palladium (as disclosed in U.S. Pat. Nos. 2,448,060,
2,566,245, 2,566,263), a sulfur sensitization method with
sulfur-containing compounds (as disclosed in U.S. Pat. No. 2,222,264), a
selenium sensitization method with selenium compounds, or a reduction
sensitization method with tin salt, thiourea dioxide, polyamine, or the
like, either singly or in combination. The high silver chloride content
emulsion of the present invention is preferably subjected to gold
sensitization or sulfur sensitization, either singly or in combination.
High silver chloride content grains having a high 111 plane proportion of
50% or more are particularly preferably subjected to sulfur sensitization,
or sulfur sensitization and gold sensitization in combination.
The emulsion layer in the silver halide photographic material of the
present invention can comprise a normal silver halide besides the high
silver chloride content grains of the present invention.
In the photographic emulsion containing high silver chloride content grains
of the present invention, the high silver chloride content grains are
present in an amount of 70% or more, preferably 90% or more, particularly
95% or more, of all the silver halide grains as calculated in terms of
projected area. In the silver halide grains to be incorporated in the
emulsion layer free of the high silver chloride content emulsion of the
present invention, high silver chloride content grains containing silver
chloride substantially free of silver iodide in an amount of 80% or more,
preferably 95% or more are present in an amount of 70% or more, preferably
90% or more, particularly 95% or more of all the silver halide grains in
the emulsion layer as calculated in terms of projected area.
The silver halide emulsion of the present invention may comprise methine
dyes other than the cyanine dye of the present invention and/or
supersensitizing agent for the purpose of extending the wavelength range
to which it is sensitive, or supersensitization. If silver halide grains
other than the silver halide grains of the present invention are contained
in the same layer or separate layers, the silver halide grains may be
spectrally sensitized with other methine dyes and supersensitizing agents,
not to mention the cyanine dye of the present invention.
Examples of a spectral sensitizing dye to be used in the present invention
include cyanine dye, merocyanine dye, complex cyanine dye, complex
merocyanine dye, holopolar cyanine dye, hemicyanine dye, styryl dye and
hemioxonol dye. Particularly useful among these dyes are cyanine dye,
merocyanine dye, and complex merocyanine dye. Any of the nuclei which are
commonly used as a basic heterocyclic nucleus for a cyanine dye can be
applied to these dyes. Examples of a suitable nucleus which can be applied
to these dyes include a pyrroline nucleus, an oxazoline nucleus, a
thiazoline nucleus, a selenazoline nucleus, a pyrrole nucleus, an oxazole
nucleus, a thiazole nucleus, a selenazole nucleus, an imidazole nucleus, a
tetrazole nucleus, a pyridine nucleus, a tellurazole nucleus and a nucleus
obtained by fusion of alicyclic hydrocarbon rings to the nucleus or a
nucleus obtained by fusion of aromatic hydrocarbon rings to the nucleus,
e.g., indolenine nucleus, benzindolenine nucleus, indole nucleus,
benzoxazole nucleus, naphthooxazole nucleus, benzimidazole nucleus,
naphthoimidazole nucleus, benzothiazole nucleus, naphthothiazole nucleus,
benzoselenazole nucleus, naphthoselenazole nucleus, quinoline nucleus, and
benzotellurazole nucleus. These nuclei may contain substituents on the
carbon atoms.
Any of the nuclei having a ketomethylene structure which are commonly used
for merocyanine dyes can be applied to a merocyanine dye or a complex
merocyanine dye. Particularly useful examples of such nuclei include 5- or
6-membered heterocyclic nuclei such as a pyrazoline-5-one nucleus, a
thiohydantoin nucleus, a 2-thiooxazoline-2,4-dione nucleus, a
thiazolidine-2,4-dione nucleus, a rhodanine nucleus, a thiobarbituric acid
nucleus, and a 2-thioselenazolidine-2,4-dione nucleus.
These sensitizing dyes can be used either singly or in combination. A
combination of sensitizing dyes is often used for the purpose of
supersensitization. Typical examples of such a combination of sensitizing
dyes are disclosed in U.S. Pat. Nos. 2,688,545, 2,977,229, 3,397,060,
3,522,052, 3,527,641, 3,617,293, 3,628,964, 3,666,480, 3,672,898,
3,679,428, 3,703,377, 3,769,301, 3,614,609, 3,837,862, and 4,026,707,
British Pat. Nos. 1,344,281, and 1,507,803, JP-B-43-4936, and
JP-B-53-12375, and JP-A-52-110618, and JP-A-52-109925.
Typical examples of supersensitizers include bispyridinium salt compounds
as disclosed in JP-A-59-142541, stilbene derivatives as disclosed in
JP-B-59-18691, water-soluble bromides as disclosed in JP-B-49-46932,
condensates of an aromatic compound and formaldehyde as disclosed in U.S.
Pat. No. 3,743,510, cadmium salts, and azaindene compounds.
The incorporation of these methine dyes into the silver halide emulsion may
be effected at any step during the preparation of the emulsion which has
heretofore been known to be suitable for this purpose. Similarly, the
incorporation of these methine dyes in the emulsion may be effected in any
way which has heretofore been known to be suitable for this purpose and in
any amount which has heretofore been known suitable for this purpose.
Specifically, the incorporation of these methine dyes in the emulsion may
be effected at the step as defined for the cyanine dye represented by
general formula (I) in the way defined for the cyanine dye in the amount
defined for the cyanine dye.
The silver halide emulsion prepared according to the present invention can
be incorporated into color photographic light-sensitive materials and
black-and-white photographic light-sensitive materials.
Specific examples of these color photographic light-sensitive materials
include color paper, color film for picture taking, and color reversal
film. Specific examples of the black-and-white photographic
light-sensitive materials include X-ray film, general purpose film for
picture taking, and film for printing light-sensitive material. In
particular, the silver halide emulsion of the present invention may be
preferably applied to in color paper.
Other additives to be incorporated in the photographic light-sensitive
material to which the emulsion of the present invention is applied are not
specifically limited. For these additives, reference can be made to
Research Disclosure Nos. 17643 (vol. 176) and 18716 (vol. 187).
These additives are listed below.
______________________________________
Kind RD 17643 RD 18716
______________________________________
1. Chemical Sensitizer
Page 23 Page 648,
right column
2. Sensitivity Page 648,
Increasing Agent right column
3. Spectral Sensitizer
Pages 23 Page 648, right
and Supersensitizer
to 24 column to page
649, right column
4. Brightening Agent
Page 24
5. Antifoggant and Pages 24 Page 649,
Stabilizer to 25 right column
6. Light-Absorbent,
Pages 25 Page 649, right
Filter Dyes and Ultra-
to 26 column to page
violet Absorbent 650, left column
7. Stain Inhibitor Page 25, Page 650, left
right column to
column right column
8. Dye Image Stabilizer
Page 25
9. Hardening Agent Page 26 Page 651,
left column
10. Binder Page 26 Page 651,
left column
11. Plasticizer and Page 27 Page 650,
Lubricant right column
12. Coating Aid and Pages 26 Page, 650,
Surface Active to 27 right column
Agent
13. Antistatic Agent
Page 27 Page 650,
right column
______________________________________
Particularly preferred among these antifoggants and stabilizers listed as
additives are azoles (e.g., benzothiazolium salt, nitroimidazoles,
nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles,
nitroindazoles, benzotriazoles, aminotriazoles), mercapto compounds (e.g.,
mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzoimidazoles,
mercaptothiadiazoles, mercaptotetrazoles (particularly
1-phenyl-5-mercaptotetrazole), mercaptopyrimidines, mercaptotriazines),
thioketo compounds such as oxazolinethione, azaindenes (e.g.,
triazaindenes, tetrazaindenes (particularly 4-hydroxy-substituted
(1,3,3a,7)tetrazaindenes), pentazaindenes), benzenethiosulfonic acid,
benzenesulfinic acid, and benzenesulfonic amide.
The preferred color couplers are nondiffusive couplers containing a
hydrophobic group called the ballast group in the molecule or polymerized
couplers. These color couplers may be either two-equivalent or four
equivalent with respect to silver ion. Colored couplers which exhibit an
effect of color correction or couplers which release a development
inhibitor upon development (so-called DIR coupler) may be incorporated
into the photographic light-sensitive material. Alternatively, colorless
DIR coupling compounds which undergo a coupling reaction to give a
colorless product and release a development inhibitor may be incorporated
into the photographc light-sensitive material.
Examples of the magenta couplers include a 5-pyrazolone coupler, a
pyrazolobenzimidazole coupler, a pyrazolotriazole coupler, a
pyrazolotetrazole coupler, a cyanoacetyl coumarone coupler and an open
chain acylacetonitrile coupler. Examples of the yellow couplers include an
acylacetamide coupler (e.g., benzoylacetoanilide, pivaloyl acetanilide).
Examples of the cyan couplers include naphthol coupler and phenol coupler.
Examples of these cyan couplers preferred because of excellent fastness of
image include phenol couplers containing an ethyl group in the
meta-position in the phenol nucleus, a 2,5-diacylamino-substituted phenol
coupler, phenol couplers containing a phenylureide group in the 2-position
and an acylamino group in the 5-position, and couplers substituted by a
sulfonamide, an amide or the like in the 5-position, as described in U.S.
Pat. Nos. 3,772,002, 2,772,162, 3,758,308, 4,126,396, 4,334,011,
4,327,173, 3,446,622, 4,333,999, 4,451,559, and 4,427,767.
Two or more of these couplers may be incorporated into the same layer to
satisfy the properties required of the light-sensitive material.
Alternatively, one of these couplers may be incorporated into two or more
different layers.
Typical examples of discoloration inhibitors include hydroquinones,
6-hydroxychromanes, 5-hydroxycoumaranes, spirochlomane, p-alkoxyphenols,
hindered phenols such as bisphenols, gallic acid derivatives,
methylenedioxanebenzenes, aminophenols, hindered amines, and ether and
ester derivatives obtained by silylating or alkylating a phenolic hydroxyl
group in these compounds. Alternatively, nickel bissalycylaldoximate
complex and nickel bis-N,N-dialkyldithiocarbamate complex may be used.
The processing of the light-sensitive material prepared according to the
present invention may be accomplished by any known method with any known
processing solution. The processing temperature is normally selected in
the range between 18.degree. C. and 50.degree. C., but may fall below
18.degree. C. or may exceed 50.degree. C. The light-sensitive material of
the present invention may be subjected to development in which silver
images are formed (black-and-white processing) or color photographic
processing comprising development in which dye images are formed.
The black-and-white developer may comprise known developing agents such as
dihydroxybenenes (e.g., hydroquinone), 3-pyrazolidones (e.g.,
1-phenyl-3-pyrazolidone), aminophenols (e.g., N-methyl-p-aminophenol),
either singly or in combination.
The color developer normally consists of an alkaline aqueous solution
containing a color developing agent. Such a color developing agent may be
a known primary aromatic amine developing agent such as phenylenediamine
(e.g., 4-amino-N,N-diethyl-aniline, 3-methyl-4-amino-N,N-diethylaniline,
4-amino-N-ethyl-N-.beta.-hydroxyethylaniline,
3-methyl-4-amino-N-ethyl-N-.beta.-hydroxyethylaniline,
3-methyl-4-amino-N-ethyl-N-.beta.-methanesulfamidoethylaniline,
4-amino-3-methyl-N-ethyl-N-.beta.-methoxyethylaniline).
Further, color developing agents as disclosed in L. F. A. Meson,
Photographic Processing Chemistry, Focal Press, 1966, pp. 226-229, U.S.
Pat. No. 2,193,015, and 2,592,364, and JP-A-48-64933 may be used.
The color developer normally may further contain a pH buffer such as a
sulfite, a carbonate, a borate and a phosphate of an alkaline metal or a
development inhibitor or fog inhibitor such as bromides, iodides and
organic fog inhibitors. If desired, the color developer may further
contain a water softener, preservatives such as hydroxylamine, organic
solvents such as benzyl alcohol and diethylene glycol, development
accelerators such as polyethylene glycol, quaternary ammonium salts and
amines, dye-forming couplers, competing couplers, fogging agents such as
sodium boron hydride, auxiliary developing agents such as
1-phenyl-3-pyrazolidone, thickening agents, polycarboxylic chelating
agents as disclosed in U.S. Pat. No. 4,083,723, and oxidation inhibitors
as disclosed in West German patent application (OLS) no. 2,622,950.
The photographic light-sensitive material which has been color-developed in
color photographic processing is normally subjected to bleach. However,
bleach may be effected simultaneously with fixation, or these two steps
may be carried out separately. Bleaching agents to be used include
compounds of polyvalent metals, e.g., iron(III), cobalt(III), chromium(IV)
and copper(II), peroxides, quinones, and nitro compounds. Examples of
these bleaching agents include ferricyanides, bichromates, organic complex
salts of iron(III) or cobalt(III) with aminopolycarboxylic acis, e.g.,
ethylenediaminetetraacetic acid, nitrilotriacetic acid, and 1,3
diamino-2-propanetetraacetic acid, or citric acid, tartaric acid, malic
acid, etc., persulfates, permanganates, and nitrosophenol. Particularly
useful among these compounds are potassium ferricyanide, ferric sodium
ethylenediaminetetraacetate(III) and ferric ammonium
ethylenediaminetetraacetate(III). In particular, ferric
ethylenediaminetetraacetate complex salts are useful both for a bleaching
solution and a blix solution.
The bleaching or blix solution may comprise bleach accelerators as
disclosed in U.S. Pat. Nos. 3,042,520 and 3,241,966 and JP-B-45-8506 and
JP-B-45-8836, and thiol compounds as disclosed in JP-A-53-65732, as well
as other various additives. The light-sensitive material which has been
subjected to bleach or blix may be then subjected to washing or to
stabilization alone.
The present invention will be further described in the following examples,
but the present invention should not be construed as being limited
thereto.
EXAMPLE 1
______________________________________
(Solution 1)
Water 1,000 cc
NaCl 5.0 g
Gelatin 32 g
(Solution 2)
AgNO.sub.3 25.6 g
Water to make 200 cc
(Solution 3)
KBr 12.54 g
NaCl 4.12 g
Water to make 200 cc
(Solution 4)
1-Benzyl-4-[2-(1-benzyl-4-pyridinio)-
0.55 g
ethyl]pyridinium dichloride
Water to make 200 cc
(Solution 5)
AgNO.sub.3 128 cc
Water to make 600 cc
(Solution 6)
KBr 62.72 g
NaCl 17.64 g
Water to make 600 cc
______________________________________
Solution 1 was heated to a temperature of 56.degree. C. Solution 2 and
Solution 3 were simultaneously added to Solution 1 with vigorous stirring
over 30 minutes. After 10 minutes, Solution 4 was added to the system.
Solution 5 and Solution 6 were simultaneously added to the system over 20
minutes. Five minutes after the completion of the addition, the
temperature of the system was lowered. A copolymer of isobutene and
monosodium maleate was added to the system as a flocculating agent. The
resulting precipitate was washed with water so that it was desalted. Water
and deionized ossein gelatin were added to the system. The pH value of the
system was then adjusted to 6.2. As a result, a monodisperse emulsion of
octahedral silver bromochloride grains with an average side length of 0.45
.mu.m, a fluctuation coefficient of 0.15 (determined by dividing the
standard deviation by the average side length: s/d), and a silver chloride
content of 30 mol % was obtained. The emulsion was then subjected to
optimum chemical sensitization with chloroauric acid and sodium
thiosulfate (this emulsion will be hereinafter referred to as "Emulsion
1").
A monodisperse emulsion of octahedral silver bromochloride grains with a
silver chloride content of 80 mol % was prepared as Emulsion 2 in the same
manner as in Emulsion 1 except that the content of KBr and NaCl in
Solution 3 were altered to 3.58 g and 8.53 g, respectively, the amount of
KBr and NaCl in Solution 6 were altered to 17.92 g and 39.67 g,
respectively, and the time during which Solutions 2 and 3 are added to the
system was each altered to 15 minutes. A monodisperse emulsion of
octahedral silver chloride grains with a silver chloride content of 100
mol % was prepared as Emulsion 4 in the same manner as in Emulsion 1
except that Solutions 3 and 6 were free of KBr, the amount of NaCl in
Solutions 3 and 6 were altered to 10.29 g and 48.48 g, respectively, and
the time during which Solutions 2 and 3 were added to the system was
altered to 8 minutes. The average grain size of Emulsions 2, 3 and 4 were
each 0.45 .mu.m. The fluctuation coefficient (determined by dividing the
standard deviation by the average side length: s/d) of Emulsions 2 and 3
were each 0.16. The fluctuation coefficient of Emulsion 4 was 0.17.
To Emulsions 1 to 4 thus prepared were each added the cyanine dye I-29 of
the present invention in the form of a methanol solution in an amount of
5.40.times.10.sup.-4 mol per mol of silver halide at a temperature of
40.degree. C. To these emulsions were then added potassium thiocyanate and
tetrazaindene compound II-1 of the present invention as set forth in Table
1 at a temperature of 40.degree. C. to prepare specimens as set forth in
Table 1.
As a support there was used a cellulose triacetate film support. The coated
amount of these emulsions were each predetermined so that the amount of
silver and gelatin reached 1.25 g/m.sup.2 and 3.0 g/m.sup.2, respectively.
An aqueous solution containing 0.1 g of sodium dodecylbenzenesulfonate,
0.22 g/l of p-sulfostyrene sodium homopolymer, 3.1 g/l of sodium salt of
2-hydroxy-4,6-dichloro-1,3,5-triazine, and 50 g/l of gelatin as main
components was simultaneously coated as an upper layer in such an amount
that the amount of gelatin reached 1.0 g/m.sup.2.
These coated specimens were each exposed to light from a tungsten light
source (color temperature: 2,854.degree. K.) through a red sharp cut
filter SC-60 available from Fuji Photo Film Co., Ltd. (filter with a
transmission of about 38% at 600 nm which transmits light of a wavelength
longer than about 580 nm) and a continuous wedge.
These specimens thus exposed were each developed with the developer having
the formulation as set forth below at a temperature of 20.degree. C. for
30 seconds, stopped, fixed, and then washed with water. These specimens
were then measured for density by means of a P type densitometer available
from Fuji Photo Film Co., Ltd. to determine red filter sensitivity (SR).
The results are set forth in Table 1.
______________________________________
Formulation of developer
______________________________________
Methol 2.5 g
L-ascorbic acid 10.0 g
Sodium chloride 0.5 g
Nabox 35.0 g
Water to make 1,000 ml
pH (20.degree. C.) 9.8
______________________________________
The reference point at which the sensitivity is determined is the density
point of "fog+0.5". The sensitivity is represented by the reciprocal of
the exposure required to give the density of "fog+0.5". The values set
forth in Table 1 are represented relative to that of Coated Specimen No.
1-1 comprising a silver bromochloride emulsion having a silver chloride
content of 30 mol % (Emulsion 1) and free of a thiocyanate and a
tetrazaindene compound as 100.
As an example of the constitution of the present invention which enables
remarkable formation of J-aggregates with a high silver chloride content
octahedral grain emulsion and silver chloride, the absorption spectrum of
Coated Specimen Nos. 1-13, 1-14 and 1-16 are shown in FIG. 1.
TABLE 1
__________________________________________________________________________
% Silver
Added amount
Added amount of
Relative
Specimen
Emulsion
chloride
of KSCN .times.
Compound II-1 .times.
red
No. No. content
10.sup.-3 mol/molAg
10.sup.-3 mol/molAg
sensitivity
Remarks
__________________________________________________________________________
1-1 (1) 30 -- -- 100 Comparative
(reference)
1-2 " " 3.0 -- 76 "
1-3 " " -- 4.0 191 "
1-4 " " 3.0 4.0 162 "
1-5 (2) 80 -- -- 41 "
1-6 " " 3.0 -- 145 "
1-7 " " -- 4.0 78 "
1-8 " " 3.0 4.0 288 Present Invention
1-9 (3) 95 -- -- 27 Comparative
1-10 " " 3.0 -- 148 "
1-11 " " -- 4.0 58 "
1-12 " " 3.0 4.0 324 Present Invention
1-13 (4) 100 -- -- 26 Comparative
1-14 " " 3.0 -- 145 "
1-15 " " -- 4.0 55 "
1-16 " " 3.0 4.0 316 Present Invention
1-17 (4) 100 -- Compound (a)
13 Comparative
1-18 " " 3.0 " 81 "
1-19 (4) 100 -- Compound (b)
51 Comparative
1-20 " " 3.0 " 129 "
__________________________________________________________________________
(a)
##STR8##
(b)
##STR9##
EXAMPLE 2
Emulsion 5 to be used in Example 2 was prepared as follows:
______________________________________
(Solution 1)
Water 1,000 cc
NaCl 5.5 g
Gelatin 32 g
(Solution 2)
Sulfuric acid (1N) 24 cc
(Solution 3)
1% Aqueous solution of 1,4-
3 cc
dimethylimidazolidine-5-thione
(Solution 4)
KBr 15.66 g
NaCl 3.30 g
Water to make 200 cc
(Solution 5)
AgNO.sub.3 32 g
Water to make 200 cc
(Solution 6)
KBr 62.72 g
NaCl 13.22 g
K.sub.2 IrCl.sub.6 (0.001%)
4.54 cc
Water to make 600 cc
(Solution 7)
AgNO.sub.3 128 cc
Water to make 600 cc
______________________________________
Solution 1 was heated to a temperature of 56.degree. C. Solution 2 and
Solution 3 were added to Solution 1. Thereafter, Solution 4 and Solution 5
were simultaneously added to the system over 30 minutes. After 10 minutes,
Solution 6 and Solution 7 were simultaneously added to the system over 20
minutes. Five minutes after the addition, the temperature of the system
was lowered. A copolymer of isobutene and monosodium maleate was added to
the system as a flocculating agent. The resulting precipitate was washed
with water so that it was desalted. Water and deionized ossein gelatin
were added to the system. The pH value and the pAg value of the system
were then adjusted to 6.2 and 7.4, respectively. As a result, a
monodisperse emulsion of cubic silver bromochloride grains with an average
side length of 0.45 .mu.m, a fluctuation coefficient of 0.08 (determined
by dividing the standard deviation by the average side length: s/d), and a
silver chloride content of 30 mol % was obtained. The emulsion was then
subjected to optimum chemical sensitization with sodium thiosulfate to
prepare Emulsion 5.
A monodisperse emulsion of cubic silver bromochloride grains with a silver
chloride content of 80 mol % was prepared as Emulsion 6 in the same manner
as in Emulsion 5 except that the content of KBr and NaCl in Solution 4
were altered to 4.47 g and 8.80 g, respectively, the amount of KBr and
NaCl in Solution 6 were altered to 17.92 g and 35.26 g, respectively, and
the time during which Solutions 4 and 5 are added to the system was
altered to 10 minutes. A monodisperse emulsion of cubic pure silver
chloride grains with a silver chloride content of 100 mol % was prepared
as Emulsion 7 in the same manner as in Emulsion 5 except that Solutions 4
and 6 were free of KBr, the amount of NaCl in Solutions 4 and 6 were
altered to 11.00 g and 44.05 g, respectively, and the time during which
Solutions 4 and 5 are added to the system was altered to 8 minutes. The
average grain size of Emulsions 6 and 7 were each 0.45 .mu.m. The
fluctuation coefficient (determined by dividing the standard deviation by
the average side length: s/d) of Emulsions 6 and 7 were 0.08 and 0.09,
respectively.
To Emulsions 5 to 7 thus prepared were added the cyanine dye I-30 of the
present invention in the form of methanol solution in an amount of
3.10.times.10.sup.-4 mol per mol of silver halide at a temperature of
40.degree. C. To these emulsions were then added sodium thiocyanate and
tetrazaindene compound II-9 of the present invention as set forth in Table
2 at a temperature of 40.degree. C. to prepare specimens as set forth in
Table 2.
As the support there was used a polyethylene terephthalate film support.
The coated amount of these emulsions were each predetermined so that the
amount of silver and gelatin reached 1.6 g/m.sup.2 and 3.0 g/m.sup.2,
respectively. An aqueous solution containing 0.1 g of sodium
dodecylbenzenesulfonate, 0.22 g/l of p-sulfostyrene sodium homopolymer,
3.1 g/l of sodium salt of 2-hydroxy-4,6-dichloro-1,3,5-triazine, and 50
g/l of gelatin as main components was simultaneously coated as the upper
layer in an amount so that the amount of gelatin reached 1.0 g/m.sup.2.
These coated specimens were each divided into two batches. One of the two
batches was exposed to light from a tungsten light source (color
temperature: 2,854.degree. K.) through a band-pass filter BPN-60 available
from Fuji Photo Film Co., Ltd. (hereinafter referred to as "Filter 1")
(having maximum transmission at about 600 nm) and a continuous wedge, and
the other was exposed to light from the tungsten light source through a
red sharp cut filter SC-66 available from Fuji Photo Film Co., Ltd.
(hereinafter referred to as "Filter 2") (filter which exhibits a
transmission of about 44% at 660 nm and transmits light of a wavelength
longer than about 640 nm) and a continuous wedge.
These specimens thus exposed were each developed with the same developer as
used in Example 1 at a temperature of 20.degree. C. for 30 seconds,
stopped, fixed, and then washed with water. These specimens were then
measured for density by means of a P type densitometer available from Fuji
Photo Film Co., Ltd. to determine sensitivity with Filter 1 and
sensitivity with Filter 2. The results are set forth in Table 2.
The reference point at which the sensitivity is determined is the density
point of "fog+0.5". The sensitivity is represented by the reciprocal of
the exposure required to give the density of "fog+0.5". The values set
forth in Table 2 are represented relative to that of Coated Specimen No.
2-1 prepared from a silver bromochloride emulsion having a silver chloride
content of 30 mol % (Emulsion 5) and free of sodium thiocyanate and
tetrazaindene compound which had been exposed to light through Filters 1
and 2, respectively, as 100.
In order to better understand the effects of the present invention, the
spectral sensitivity distribution spectrum and spectral absorption
spectrum of Coated Specimens 2-1, 2-2 and 2-3 which have been subjected to
the same develoment are shown in FIG. 2 and FIG. 4, respectively, and the
spectral sensitivity distribution spectrum and spectral absorption
spectrum of Coated Specimens 2-7, 2-8 and 2-9 which have been subjected to
the same development are shown in FIG. 3 and FIG. 5, respectively.
TABLE 2
__________________________________________________________________________
Emulsion No.
and % Silver
Added amount
Added amount
Relative
Specimen
chloride
of NaSCN .times.
of Compound II-9 .times.
sensitivity
No. content
10.sup.-3 mol/molAg
10.sup.-3 mol/molAg
Filter 1
Filter 2
Remarks
__________________________________________________________________________
2-1 (5)
30 -- -- 100 100 Comparative
(reference)
(reference)
2-2 " " 2.7 -- 83 91 "
2-3 " " 2.7 3.6 174 219 "
2-4 (6)
80 -- -- 135 87 "
2-5 " " 2.7 -- 43 85 "
2-6 " " 2.7 3.6 132 309 Present Invention
2-7 (7)
100 -- -- 158 83 Comparative
2-8 " " 2.7 -- 41 79 "
2-9 " " 2.7 3.6 126 324 Present Invention
2-10
(7)
100 2.7 Compound (b) 3.6
37 76 Comparative
2-11
(7)
100 2.7 Compound (c) 3.6
68 120 Comparative
__________________________________________________________________________
(c)
##STR10##
EXAMPLE 3
______________________________________
(Solution 1)
Water 1,000 cc
NaCl 10 g
1-Benzyl-4-[2-(1-benzyl-4-
0.85 g
pyridinio)ethyl]pyridinium
chloride
Gelatin 30 g
(Solution 2)
AgNO.sub.3 25.6 g
Water to make 200 cc
(Solution 3)
KBr 3.58 g
NaCl 11.05 g
Water to make 200 cc
(Solution 4)
AgNO.sub.3 128 cc
Water to make 600 cc
(Solution 5)
KBr 17.92 g
NaCl 47.24 g
Water to make 600 cc
______________________________________
Solution 1 was heated to a temperature of 56.degree. C. Solution 2 and
Solution 3 were simultaneously added to Solution 1 with vigorous stirring
in 15 minutes. After 10 minutes, Solutions 4 and 5 were simultaneously
added to the system over 20 minutes. Five minutes after the completion of
the addition, the temperature of the system was lowered. A copolymer of
isobutene and monosodium maleate was added to the system as a flocculating
agent. The resulting precipitate was washed with water so that it was
desalted. Water and deionized ossein gelatin were added to the system. The
pH value and pAg value of the system were then adjusted to 6.2 and 7.3,
respectively. As a result, a monodisperse emulsion of hexagonal tabular
silver bromochloride grains with an average diameter of 1.12 .mu.m, an
average diameter/thickness ratio of 14, and a silver chloride content of
80 mol % was obtained. The emulsion was then subjected to optimum chemical
sensitization with chloroauric acid and sodium thiosulfate (this emulsion
will be hereinafter referred to as "Emulsion 8").
A monodisperse emulsion of tabular pure silver chloride grains with a
silver chloride content of 100 mol % was prepared as Emulsion 9 in the
same manner as in Emulsion 8 except that Solutions 3 and 5 were free of
KBr, the content of NaCl in Solutions 3 and 5 were altered to 12.81 g and
56.05 g, respectively, and the time during which Solutions 2 and 3 are
added to the system was altered to 8 minutes. Emulsion 9 thus obtained
exhibited an average grain diameter of 1.14 .mu.m and an average
diameter/thickness ratio of 12.7.
To Emulsion 8 thus prepared was added the cyanine dye I-15 of the present
invention in the form of methanol solution in an amount of
5.40.times.10.sup.-4 mol per mol of silver halide at a temperature of
40.degree. C. The material was then divided into four batches. To these
emulsions were then added potassium thiocyanate and tetrazaindene compound
II-2 of the present invention as set forth in Table 3 at a temperature of
40.degree. C. Emulsion 9 previously prepared was then divided into two
batches. To one of the two batches was added the cyanine dye I-15 in an
amount of 5.40.times.10.sup.-4 mol per mol of silver halide. To the other
batch was added the cyanine dye I-4 of the present invention in an amount
of 6.00.times.10.sup.-4 mol per mol of silver halide. The two batches were
each further divided into two batches. To these batches were each added
potassium thiocyanate and compounds as set forth in Table 3 in the amounts
as set forth in Table 3 at a temperature of 40.degree. C. After 20
minutes, to these batches were each added an emulsion dispersion obtained
by dissolving
1-(2,4,6-trichlorophenyl)-3-(2-chloro-5-tetradecanoylaminoanilino)-5-pyraz
olone as magenta coupler and Cpd-1 and Cpd-2 as dye stabilizers in ethyl
acetate, biscyclohexyl phthalate and tritolyl phosphate, and then
emulsion-dispersing the solution in a 10% aqueous gelatin solution
containing 10 ml of 10% sodium dodecylbenzenesulfonate in an amount of
138.9 g per mol of silver halide as calculated in terms of the coupler.
The emulsions thus prepared were each coated on a polyethylene
double-laminated paper support in such an amount that the amount of silver
and gelatin reached 0.35 g/m.sup.2 and 1.50 g/m.sup.2, respectively. On
the emulsion layer was coated a protective layer having a gelatin content
of 1.50 g/m.sup.2. As gelatin hardener there was incorporated the sodium
salt of 2-hydroxy-4,6-dichloro-1,3,5-triazine in each layer.
##STR11##
Coated Specimens 3-1 to 3-8, which comprised the cyanine dye I-15, were
then exposed to light from a tungsten light source (color temperature:
2,854.degree. K.) through a sharp cut filter SC-52 available from Fuji
Photo Film Co., Ltd. (which transmits light of a wavelength longer than
about 500 nm) and a continuous wedge. Coated Specimens 3-9 to 3-12, which
comprised the cyanine dye I-4, were exposed to light from the tungsten
light source through a sharp cut filter SC-46 (which transmits light of a
wavelength longer than about 450 nm) and a continuous wedge.
The specimens thus exposed were then subjected to color development in the
following steps:
______________________________________
Processing Replenishment
Tank
step Temperature
Time rate* capacity
______________________________________
Color 35.degree. C.
35 sec. 161 ml 17 l
development
Blix 30-35.degree. C.
45 sec. 215 ml 17 l
Rinse 1 30-35.degree. C.
20 sec. -- 10 l
Rinse 2 30-35.degree. C.
20 sec. -- 10 l
Rinse 3 30-35.degree. C.
20 sec. 350 ml 10 l
Drying 70-80.degree. C.
60 sec.
______________________________________
(The rinse step was effected in a countercurrent process wherein the wate
flowed backward from Rinse 3 to Rinse 1.)
*per m.sup.2 of lightsensitive material
The various processing solutions had the following compositions:
COLOR DEVELOPER
______________________________________
Running
Solution Replenisher
______________________________________
Color developer
Water 800 ml 800 ml
Ethylenediamine-N,N,N-
1.5 g 2.0 g
tetramethylenephosphonic
acid
Triethanol amine 8.0 g 12.0 g
Sodium chloride 1.4 g --
Potassium carbonate 25.0 g 25.0 g
N-ethyl-N-(.beta.methanesul-
5.0 g 7.0 g
fonamidoethyl)-3-methyl-4-
aminoaniline sulfate
N,N-bis(carboxymethyl)
5.5 g 7.0 g
hydrazine
Brightening agent (WHITEX
1.0 g 2.0 g
4B, available from Sumitomo
Chemical Co., Ltd.)
Water to make 1,000 ml 1,000
ml
pH (25.degree. C.) 10.05 10.45
Blix solution (the running solution was used also as the replenisher)
Water 800 ml
70% Ammonium thiosulfate
100 ml
Sodium sulfite 17 g
Ammonium ethylendiamine-
55 g
tetraacetato ferrate
Disodium ethylenediamine-
5 g
tetraacetate
Ammonium bromide 40 g
Water to make 1,000 ml
pH (25.degree. C.) 6.0
______________________________________
Rinse Solution (The Running Solution Was Used Also As The Replenisher)
Ion-exchanged water (calcium and magnesium concentrtion: 3 ppm or less
each)
The evaluation of photographic properties was carried out as follows:
These specimens were measured for magneta color density by means of a P
type densitometer available from Fuji Photo Film Co., Ltd. through a green
filter to determine sensitivity and fog. The reference point at which the
sensitivity is determined is the density point of "fog+1.0". The
sensitivity is represented by the reciprocal of the exposure required to
give the density of "fog+1.0". The values of Coated Specimens 3-1 to 3-8
are represented relative to that of Coated Specimen No. 3-1 prepared free
of potassium thiocyanate and a tetrazaindene compound as 100. The values
of Coated Specimens 3-9 to 3-12 are represented relative to that of Coated
Specimen No. 3-9 as 100.
Further, as an example of the constitution of the present invention which
enables remarkable formation of J-aggregates with a high silver chloride
content tabular grain emulsion and silver chloride, the absorption
spectrum of Coated Specimen Nos. 3-5, 3-6 and 3-8 are shown in FIG. 6.
TABLE 3
__________________________________________________________________________
Kind of tetraza-
Emulsion No.
Added amount
indene compound and
Relative
Specimen
and % silver
of KSCN .times. 10.sup.-3
added amount thereof .times. 10.sup.-3
spectral
No. chloride content
mol/mol Ag
mol/mol Ag sensitivity
Remarks
__________________________________________________________________________
3-1 (8) 80 -- -- 100 Comparative
(reference)
3-2 (8) 80 3.5 -- 490 "
3-3 (8) 80 -- II-2 5.0 204 "
3-4 (8) 80 3.5 II-2 5.0 1318 Present Invention
3-5 (9) 100 -- -- 95 Comparative
3-6 (9) 100 3.5 -- 468 "
3-7 (9) 100 -- II-20 4.5 178 "
3-8 (9) 100 3.5 II-20 4.5 1072 Present Invention
3-9 (9) 100 -- -- 100 Comparative
(reference)
3-10
(9) 100 3.5 -- 4467 "
3-11
(8) 100 -- III-1 4.5 214 "
3-12
(9) 100 3.5 III-1 4.5 10470 Present Invention
__________________________________________________________________________
EXAMPLE 4
Emulsion 4 as used in Example 1 (an emulsion of octahedral pure silver
chloride grains) which had not yet been subjected to chemical
sensitization was used in this example. To this emulsion was added the
cyanine dye I-50 of the present invention in an amount of
4.25.times.10.sup.-4 mol and potassium thiocyanate as set forth in Table 4
at a temperature of 70.degree. C. After 30 minutes, the system was cooled
to a temperature of 60.degree. C. The emulsion was then ripened with
sodium thiosulfate and chloroauric acid for 30 minutes to obtain optimum
sensitivity. To the emulsion was then added the tetrazaindene compound
II-1 as set forth in Table 4.
In the same manner as in Example 1, the emulsion was coated on a support,
and a protective layer comprising gelatin as main component was then
coated thereon.
These coated specimens were each exposed to light from a tungsten light
source (color temperature: 2,854.degree. K.) through a red sharp cut
filter SC-72 available from Fuji Photo Film Co., Ltd. (which exhibits a
transmission of about 42% at 720 nm and transmits light of a wavelength
longer than about 680 nm) and a continuous wedge.
These specimens thus exposed were developed in the same manner as in
Example 1. These specimens were then measured for density by means of a P
type densitometer available from Fuji Photo Film Co., Ltd. to determine
sensitivity with an infrared filter in the same manner as in Example 1.
The results are set forth in Table 4. The spectral sensitivity
distribution spectrum and absorption spectrum of these specimens are shown
in FIG. 7 and FIG. 8, respectively.
TABLE 4
__________________________________________________________________________
Added amount
Added amount of
Specimen
of KSCN .times. 10.sup.-3
Compound II-1 .times. 10.sup.-3
No. mol/mol Ag
mol/mol Ag Relative sensitivity
Remarks
__________________________________________________________________________
4-1 -- -- 100 Comparative
(reference)
4-2 3.0 -- 2512 "
4-3 -- 3.9 282 "
4-4 3.0 3.9 5754 Present Invention
__________________________________________________________________________
EXAMPLE 5
A monodisperse emulsion of cubic silver chloride grains with an average
side length of 0.73 .mu.m and a standard deviation of 0.12 was prepared in
the same manner as Emulsion 7 as used in Example 2 (emulsion of pure
silver chloride grains). To this emulsion was added an emulsion of finely
divided silver bromide grains in an amount of 0.01 mol per mol of silver
chloride for ripening. The emulsion was then heated to a temperature of
70.degree. C. To the emulsion was then added the cyanine dye I-46 of the
present invention in an amount of 3.60.times.10.sup.-4 mol and potassium
thiocyanate as set forth in Table 5. After 30 minutes, the system was
cooled to a temperature of 60.degree. C. The emulsion was then ripened
with sodium thiosulfate and chloroauric acid to obtain optimum
sensitivity. To the emulsion was then added the tetrazaindene compound
II-1 as set forth in Table 5.
The emulsion was coated on a support, and a protective layer comprising
gelatin as a main component was then coated thereon in the same manner as
in Example 1 except that the coated amount of silver was 2.65 g/m.sup.2.
These coated specimens were each exposed to light from a tungsten light
source (color temperature: 2,854.degree. K.) through a red sharp cut
filter SC-74 available from Fuji Photo Film Co., Ltd. (which exhibits a
transmission of about 47% at 740 nm and transmits light of a wavelength
longer than about 700 nm) and a continuous wedge.
These specimens thus exposed were developed in the same manner as in
Example 1. These specimens were then measured for density by means of a P
type densitometer available from Fuji Photo Film Co., Ltd. to determine
sensitivity with an infrared filter in the same manner as in Example 1.
The results are set forth in Table 5. The absorption spectrum of these
coated specimens are shown in FIG. 9.
TABLE 5
__________________________________________________________________________
Added amount
Added amount of
Specimen
of KSCN .times. 10.sup.-3
Compound II-1 .times. 10.sup.-3
No. mol/mol Ag
mol/mol Ag Relative sensitivity
Remarks
__________________________________________________________________________
5-1 -- -- 100 Comparative
(reference)
5-2 1.5 -- 112 "
5-3 -- 3.2 347 "
5-4 1.5 3.2 468 Present Invention
__________________________________________________________________________
It has been disclosed herein that when a silver halide emulsion comprising
high silver chloride content grains contains at least one cyanine dye
represented by the general formula (I), at least one thiocyanate compound
and at least one of compound represented by the general formula (II),
(III) or (IV), it provides a remarkably strong formation of J-aggregates
of cyanine dye from which a high spectral sensitivity can be obtained.
As shown in FIG. 1, the use of cyanine dye alone does not provide a strong
formation of J-aggregates on such a high silver chloride content emulsion.
The resulting J-band absorption is weak. The use of a cyanine dye in
combination with thiocyanate provides an increase in J-band absorption
with a decrease in the absorption in M-band. As a result, J-band type
spectral sensitization can be obtained, drastically increasing spectral
sensitization in J-band as shown in Table 1. Further, as disclosed herein,
the combined use of a tetrazaindene compound provides further remarkable
improvements in spectral sensitivity without impairing the strengthened
J-band. Such a phenomenon is not observed on emulsions comprising silver
bromide as a main component. In particular, as can be seen in Specimens
1-1 to 1-4 prepared from an emulsion of octahedral silver bromochloride
grains with a silver chloride content of 30 mol % as set forth in Table 1,
even the use of a thiocyanate compound with a cyanine dye does not provide
an increase in sensitivity, but rather provides a decrease in sensitivity.
As is well known, such an emulsion of silver bromochloride grains
comprising silver bromide as main component has been observed to provide a
strong formation of J-band. Unlike high silver chloride content grains,
such an emulsion exhibits no increase in J-band absorption, rather some
decrease in J-band absorption, by the combined use of a thiocyanate
compound (Specimens 1-1 and 1-2 exhibit little change in J-band
absorption). Therefore, such an emulsion exhibits only an undesirable
effect of reducing sensitivity due to the addition of a thiocyanate
compound without increasing the percentage of light absorption. If such an
emulsion of cubic silver bromochloride grains comprising silver bromide as
a main component is used together with a tetrazaindene compound and a
cyanine dye, it exhibits an increase in sensitivity even upon rapid
development as is well known.
When only a tetrazaindene compound is incorporated in a high silver
chloride content emulsion, the emulsion exhibits a remarkable increase in
its inherent sensitivity. However, it has been known that when the
tetrazaindene compound is incorporated in combination with a cyanine dye
into the high silver chloride content emulsion, it inhibits the adsorption
of the dyes and the formation of j-aggregates, causing little increase or
some decrease in spectral sensitivity, as shown in Table 1. However, the
combined use of a thiocyanate compound can provide an extremely high
spectral sensitivity in J-band with a high silver chloride content
emulsion, which has been unprecedented with a silver bromochloride
emulsion comprising silver bromide as a main component.
On the other hand, the use of other azole compounds only causes a reduction
in sensitivity (Specimens 1-18 and 1-20).
With the developer in Example 1, the specimens prepared from high silver
chloride content emulsions of the present invention can be developed in 20
seconds while the specimens prepared from silver bromochloride emulsions
with a silver chloride content of 30 mol % cannot be yet developed in 20
seconds. The latter specimens can be developed in 2 minutes. The resulting
relative sensitivity is about 1.4 times that obtained by 30-second
development as set forth in Table 1. The former specimens of the present
invention can be developed in a very short period of time. The resulting
relative sensitivity is about the same as or higher than that of the
latter specimens.
Table 2 shows the results obtained with cubic grain emulsions. Cubic grain
emulsions exhibit a formation of J-aggregates which is weak but stronger
than that of octahedral grain emulsions even with high silver chloride
content emulsions and show considerable J-band absorption as shown in FIG.
5. Therefore, unlike octahedral grain emulsions, cubic grain emulsions
exhibit a reduction in sensitivity in J-band (sensitivity with Filter 2)
even with the combined use of a cyanine dye of the present invention and a
thiocyanate compound as in the case where a silver bromochloride emulsion
comprising silver bromide as a main component (Specimen 2-2). However, the
additional combination of a tetrazaindene compound provides a very large
increase in sensitivity as compared with that obtained with a silver
bromochloride emulsion comprising silver bromide as a main component
(Specimens 2-6 and 2-9), which has been unprecedented with the combined
use of other azole compounds. Further, in FIGS. 5 and 6, cubic grain
emulsions show a small change in the absorption in the vicinity of 600 nm,
which corresponds to M-band range. However, the high silver chloride
content emulsions exhibit a higher sensitivity in the vicinity of 600 nm
with a cyanine dye alone than silver bromochloride emulsions comprising
silver bromide as a main component. On the other hand, the specimens
according to the present invention (Specimens 2-6 and 2-9) exhibit a lower
sensitvity in the vicinity of 600 nm than Specimen 2-3 prepared from a
silver bromochloride emulsion comprising silver bromide as main component,
realizing a spectral sensitivity distribution with a high J-band
sensitivity/M-band sensitivity ratio. Such desirable results in
development will be better understood from the spectral sensitivity
distribution spectrum shown in FIGS. 2 and 3. The technique by which high
sensitivity can be provided only in the desired wavelength range while
keeping the sensitivity in other wavelength ranges as low as possible is
essential to the enhancement of safety to safelight or the inhibition of
color stain in designing color multi-layer light-sensitive materials to
provide a sharp color photograph.
As shown in Tables 3, 4 and 5, and FIGS. 5 to 9, the constitution of the
present invention with a high silver chloride content emulsion can
similarly provide a high J-band sensitization.
Further, although it is extremely difficult for a high silver chloride
content emulsion having 111 plane to provide J-band sensitization with a
cyanine dye, the constitution of the present invention provides an easy
realization of high J-band sensitization. Dicarbocyanine dyes have
heretofore been known to exhibit M-band type sensitization. However, it
has not been well known that discarbocyanine dyes provide J-band
sensitization, except for one report that some dicarbocyanine dyes exhibit
J-band sensitization on a silver bromoiodide emulsion.
One of the inventors disclosed a technique by which some dicarbocyanine
dyes contained in the cyanine dye represented by general formula (I) can
realize J-band sensitization even on various silver halide emulsions such
as silver bromoiodide, silver bromide, silver chloride and silver
bromochloride. The inventors found the technique of the present invention
by which even higher sensitivity can be provided only in J-band range up
to infrared range on the most difficult high silver chloride content
emulsions.
While the invention has been described in detail and with reference to
specific embodiments thereof, it will be apparent to one skilled in the
art that various changes and modifications can be made therein without
departing from the spirit and scope thereof.
Top